The present invention relates to a composite part of a piezo-electric resonator and a condenser intergrated and housed in a case and a method of producing said composite part.
As shown in FIG. 1, in the conventional oscillating circuit using a piezo-electric resonator therein, a piezo-electric resonator 12 is connected with a signal-inventor 11 in parallel and the ends of said piezo-electric resonator 12 are respectively connected by load condensers C.sub.1, C.sub.2, and ground.
However, since said signal-inventor 11 is generally constructed from one condenser and said piezo-electric resonator 12 and load condensers C.sub.1, C.sub.2 are three outside parts in all, there are the following disadvantages:
(I) Since three parts are required for constructing the oscillating circuit, the management of parts becomes complicated.
(II) Since three parts are independently attached on the outside, the actual space of an oscillating circuit is increased, whereby a wider area is required for the substrate.
(III) Although the attachment of parts is achieved by soldering, it is preferable in respect of performance of the oscillating circuit that the number of places to be soldered is as small as possible. Where three outside parts are attached, the number of places to be soldered is increased, whereby it is difficult to produce an oscillating circuit, and further, the resulting oscillating circuit is wanting in fidelity. In addition, insufficient soldering leads to no oscillation or nonuniform oscillation.
(IV) Since outside parts are attached, the dispersion of said load condensers C.sub.1, C.sub.2 in capacity is multiplied by the dispersion of said piezo-electric resonator 12 in capacity to produce a dispersion in oscillating frequency, whereby the oscillating frequency is remarkably deteriorated in accuracy.
(V) Since a piezo-electric resonator, which is superior in the accuracy of frequency, must be produced by the vacuum deposition of Ag or the like on an excitation electrode while measuring oscillating frequency, an expensive large-sized vacuum deposition apparatus is required, whereby productivity is small.